Safety button



Jan. 13, 1953 BLAKEMQRE 2,625,052

SAFETY BUTTON Filed NOV. 14. 1949 IN V EN TOR.

4440 0 BLAKE/MORE Patented Jan. 13, 1953 UNITED STATES PATENT OFFICE SAFETY BUTTON Elmo D. Blakemore, Flint, Mich.

Application November 14, 1949, Serial No. 126,967

Claims. 1

This invention relates to electric switch safety buttons and in particular to improvements in electric switch buttons which are incapable of activation accidentally and which are especially suitable for use in conjunction with punch presses and other hazardous machinery.

The desirability of providing safety devices in conjunction with the operating controls of punch presses is well recognized and various safety devices are well known to those familiar with the art such as dual buttons requiring one button to be depressed by each hand of the operator; wrist cuffs and cables preventing the operator from putting his hands in the area of the press, etc.

However, in actual use, the dual buttons have been found to slow up the operator so that he locks one button down and then uses the other to operate the press despite the vigilance of management, unions, and safety ofiicers. When one button is locked down, the press can be operated by pressing the other button which operation can be accidental such as by leaning on the open button, a tool falling on the open button, a piece of stock falling on the open button, or another workman unknowingly pressing the button in assisting the operator in some task such as cleaning the punch, etc., and numerous accidents have occurred in this manner with resulting loss of members and life.

With the foregoing in view, the primary object of the invention is to provide a switch control safety actuating button which is incapable of operation under direct pressure such as by a person accidentally leaning on or pressing the button or by a tool, piece of stock, or crane accidentally pressing or falling on the button.

An object of the invention is to provide a. safety button which must first be rotated before it can be depressed to make the necessary contact to operate the press. 7

An object of the invention is to provide a safety button which normally maintains an inoperative position unless rotated and held in the operative position.

An object of the invention is to provide a safety button which is capable of automatically returning to an inoperative position after it has been rotated to the operative position.

An object of the invention is to provide a safety button with a strong safety mechanism capable of withstanding excessive forces tending to depress the button to make contact in the switch.

Another object of the invention is to provide a mechanism having only a few parts, simple in construction, and inexpensive to manufacture.-

These and other objects will become apparent by reference to the following description of the switch actuating safety button embodying the invention taken in connection with the accompanying drawing, in which:

Fig. 1 is a vertical sectional View taken across the longitudinal center of the device showing the depressed contact making condition in dotted lines.

Fig. 2 is a cross-sectional view of Fig. 1 taken on the line 2-2 thereof.

Fig. 3 is a side elevational view of a modified structure, partly in cross-section, showing optional construction; and

Fig. 4 is a cross-sectional view of Fig. 3 taken on the line 44 thereof Referring now to the drawing wherein like numerals refer to like and corresponding parts throughout the several views, the safety button disclosed therein to illustrate the invention comprises a housing or face plate I0 mountable on a switch box I I having a, connector I2 capable of operating the switch, not shown, within the box II, a button I4 disposed above or outside the housing or face plate I0 having a shank or sleeve portion I5 extending through the housing I0 and pivotally attached to the switch connector I2, a pin or dog I6 on the underside of the button I4 extending toward the housing or face plate I0 radially indexed with a pin receiving opening or interruption H in the housing or face plate II! but normally out of circumferential phase with the opening I! so as to prevent the button I2 from being depressed by the pin or dog I6 contacting the face of the housing or face plate ID, a dog or stop I8 on the housing or face plate I0 removed from the opening H, a spring I9 anchored in the housing or face plate I0 and secured to the button I4 normally urging the pin I6 against the stop I8 out of phase with the opening I1, and a stop 20 immediately adjacent the opening H for circumferentially indexing the pin I6 with the opening I! when the button I 4 is manually rotated against the spring I9 to position the pin I6 so that it will enter the opening I! thereby allowing the button I4 to be depressed to operate the switch via the connector I2.

More particularly, referring to Figs. 1 and 2, the housing or face plate I0 is provided with a small pin receiving aperture or interruption I1, a large aperture for receiving the shank or sleeve I5 of the button I4; the switch connector I2 is pivotally mounted at 2| on the housing l0 via the extensions or ears 22 while the connector I2 is provided with a hooked end 23 for attachment to the switch, not shown, as well known in the art; a stud 24 is mounted on the connector I 2 by means of a rivet or bolt 25, an axial bore 26 is provided in the top of the stud 25 to hold the ball bearing 21 so that the ball bearing 21 extends slightly above the top of the stud 24 providing a pivot point, a blind sleeve or hollow shank I5 01' 28 surrounds the stud 24, and a hardened plate 23 fitted within the sleeve 28 rides on the ball bearing 21 with the cap-like portion of the button I4 supporting the pin or dog I6 and retaining the end 3| of the spring I9 with the other end 32 of the spring I9 being retained in the housing or face plate I; the stud 24 is equipped with an annular groove 33 in its side periphery and the sleeve or shank'28 is provided with slot 34 leading to the groove 33 and with an annular groove leading to the slot 34 so that the spring clip 35 may be disposed via the slot 34 in the-groove 33 securing the sleeve *or shank I5 or 28 on the stud 24 with the spring clip 35 partially surounding the shank I5 or 28 and lying in the groove thereof thereby securing itself in locked relation.

Relative to the modification shown in Figs. 3 and 4, it will be noted that the shank- 28A is solid andpivotallymounted on the connector I2 'via a shoulder bolt A, that two pins I6 are provided and that the stops ISA and 20A are positioned above the surface of the face plate I0.

While the rotational travel of the button I4 under the torsion of the spring I9 has been previously described as being limited by a stop I8 or ISA, it is obvious that the spring I9 can be soadjusted as to limit the travel of the button I4 obviating the necessity of a stop I8 or I8A. In other words, the spring I9 is so designed to rotate the button I4 a pre-determined distance so as to position a pin or dog I6 out of phase with the opening or interuption II.

It is obvious that the button I4 can be equipped withone, two, or more pins or dogs I6 with the plate I0 being provided with an equal number of openings, interruptions, or apertures I! for receiving the pins I6 therein and the stops I8 and 20 and I8A and 23A can be either omitted, raised above the surface of the plate I0, or recessed in the face of the plate I0 utilizing the surrounding area of the plate III for the stop. The button I4 may be rotatably 'mounted by a pivotal relation between the shank 28 and the stud 24, or by a pivoted relation between the shank 28A and the connector I2 as shown in the drawing or by pivotally mounting the head of the button I4 on the shank 28 or by allowing the connector I2 to pivot with the button I4 and shank 28. In other words the button I4 may be positioned rotatab'ly relative to the housing or face plate III in other ways than illustrated in the figures and still be within the scope of the invention and the switch connector I2 can be hingedly connected as shown or freely plungably mounted as well known in the art utilizing springs and other well known devices. The inventive electrical switch safety button is preferably completely assembled and the connector I2 is then linked with the switch when the device is attached to the switch box II by means of the bolts'40.

In operation, the device having been assembled and mounted, the operator places the stock or form in the press and then places his hand on the button I4 and rotates the button I4 in relation to the plate or housing I0 until the dogs LII or pins I6 contact a stop 20 or 20A which positions the pin I6 circumferentially with the pin receiving aperture I! in the plate or housing I0 and the operator may then depress the button I4 actuating the connector I2 to operate the switch, not shown, as the pins are received in the openings I1 allowing the button to be depressed towards the face of the plate or housing I0.

It will be understood that in the operation of the device, the usual action of the pin or dog It relative to the housing I0 and the interrupmen I! is such that the pin or dog I6 drops into the interruption I'I prior to contacting the stop 20 or 20A due to the fact that the operator is pressing the button I4 downwardly as seen in the drawings with the dog I6 riding on the housing III as the operator rotates the button I4 so that upon the dog It becoming indexed with the interruption II, the dog I6 drops into the interruption I'I- thereby obviating the stop 20 or'20A.

Upon completion of the-machine operation, the operatorremoves his hand from the button and the spring I9 urges the button outwardly from the face of the plate or housing I0 so that the pins I6 are extracted from the opening I1 and the spring I9 then rotates the button I4 moving the pins out of circumferential indexed relation with the'op'enings I! which movement is limited by the stops IB- and 18A positioning the pins I6 over the face of the plate orhousing Iliout of indexed relation- With the opening I! so that-any direct pressure exerted on the button I4 is transmitted via the pins It to the face of the housing or pla'teIO thereby preventing the button from being depressed towards the face of the housing I0 rendering the button mechanically inoperative to actuate the connector I2 to operate the switch, not shown.

In that the device automatically returns to'an inoperative position and in that the'device must be manually rotated against the spring I9 to index the pin I 6 with the pin receiving opening II, it is obvious that accidental pressure applied 'to the button I4 such as by the operator leaning on the button or by a piece of steel'or a tool accidentally pressing on the button will not cause the button to "move toward the face of the plate or housing II) to actuate the connector I2 to operate the switch thereby eliminating the danger of accidentally operating the punch press to which the device is attached.

Although but one embodiment and one modification of the invention has been shown'and described in detail and other modifications briefly described, it 'is obvious that many changes may be made in the size, shape, detail and arangements of the elements of the invention within the scope of the appended claims.

I claim:

1. A switch button comprising a housing having a large aperture and a small aperture slightly removed from the large aperture, a stop on said housing face at the small aperture for circumferentially aligning a pin with the small aperture, a stop on said housing face removed from the small aperture for circumferentially positioning a pin out of alignment with the small aperture. a switch connecting and actuating member within said housing adapted to operate an electrical switch, a stud mounted on said member extending through the large aperture of said housing having a'blind axial bore in the outer end thereof and an annular groove in the side periphery thereof, a ball bearing disposed in the blind bore'of said stud resting on the bottom thereof and extending outwardly beyond the end of said stud providing an axially disposed pivot point, a blind sleeve rotatably surrounding said stud having a slot through the side thereof leading to the annular groove in said stud and a groove in its outer peripheral surface located opposite the slot therein, a spring clip secured in groove of said sleeve and lying in the slot of said sleeve and extending into the groove of said stud r0- tatably securing said sleeve to said stud and anchoring said sleeve in relation to said stud against endwise movement under normal use, a hardened disc disposed between the bottom of said blind sleeve and said ball bearing providing a pivoting surface for said sleeve in relation to said stud, a palm button mounted on said sleeve, a pin extending from the back of said palm button toward said housing positioned between said stops and radially aligned with the small aperture of said housing and adapted to be received therein, and a torsion spring surrounding said sleeve anchored to said housing and anchored to said button normally exerting rotational force on said button to urge said pin against said stop removed from the small aperture of said housing positioning said pin out of circumferential alignment with the small aperture so that said pin prevents said button from being depressed by contacting the face of said housing; said button being manually rotatable with said sleeve against said spring to circumferentially align said pin with the small aperture of said housing by contacting said stop at the small aperture with said pin so that the button may be manually depressed out of contact with said housing with said pin entering the small aperture of said housing.

2. A switch button comprising a housing having a large aperture and at least one small aperture adjacent the large aperture in the face thereof, a stop on said housing next adjacent each small aperture, a stop on said housing removed from each small aperture, a switch connecting and actuating member within said housing adapted to be attached to an electrical switch, a stud secured to said member extending through the face of said housing via the large aperture therein having a blind axial bore in the outer end thereof and an annular groove in the side periphery thereof, a ball bearing disposed in the blind bore of said stud resting on the bottom thereof and extending slightly outwardly of the end of said stud providing an axially disposed pivot point, a blind sleeve surrounding said stud having a slot in the side wall thereof opposite and leading to the annular groove in said stud and adapted to rotate relative to said stud and a groove in its outer periphery opposite to said slot, a hardened annular plate disposed between the back wall of said blind sleeve and said ball bearing adapted to pivot with said sleeve on said ball bearing, a spring clip locking said sleeve on said stud disposed in said sleeve slot and said stud groove and secured in said sleeve groove, a palm button integral with said sleeve, at least one dog on said button extending toward said housing lying between said stops and radially aligned with a small aperture in said housing and adapted to enter same at a certain circumferential position of said button and a torsion spring anchored on said housing surrounding said sleeve and anchored in said button adapted to rotate said dog out of alignment with said housing small aperture and capable of allowing said button to be manually rotated to align said dog with said housing small aperture so that said button may be manually depressed withsaid dog entering said housing small aperture.

3. A switch safety button comprising a plate having a button shank receiving opening and a safety pin receiving opening, means associated with said plate suitable to be connected to a switch to operate same, a button shank pivotally mounted on said means and extending through said face plate via the shank receiving opening thereof, a button cap on said shank, a first stop on said plate removed from the pin receiving opening, a secured stop on said plate at the pin receiving opening, a safety pin on said cap axially aligned with the pin receiving. opening disposed between said stops, and a spring normally urging said pin away from said opening against said first stop so that said pin prevents said button from being depressed by contacting said plate; said button being manually rotatable against said spring to move said pin against said second stop at said pin receiving opening so that said button may be depressed to operate said switch with said pin entering the pin receiving opening.

4. A switch safety button comprising a face plate having a safety pin receiving opening, a switch actuating mechanism associated with said plate, a rotatably mounted button on said switch actuating mechanism extending through said plate a first stop on said plate removed from the opening, a second stop on said plate at the opening, a pin on said button disposed between said stops, and a spring normally rotatably urging said button so that said safety pin abuts said first stop out of phase with the opening with said pin preventing saidbutton from being depressed to actuate the switch by contacting said plate; said button being manually rotatable against said spring to position said pin against said second stop so that said pin enters said opening thereby allowing said button to be depressed to actuate the switch.

5. A switch safety button comprising a plate having a pin receiving opening, switch actuating means associated with said plate, a rotatably mounted button adapted to operate said means, a pin on said button normally preventing depressing said button to operate same, and a spring normally torsionally positioning said button and said pin in inoperative condition; said button being manually rotatable to position said pin at the pin receiving opening in said plate so that said pin enters the opening allowing the button to be depressed.

6. In a device as set forth in claim 5, a stop normally indexing said pin out of phase with the pin receiving opening placing the device in inoperative condition.

7. In a device as set forth in claim 5, a stop for indexing said pin in place with the pin receiving opening.

8. An electrical switch actuating safety button comprising a rotatable switch actuating plunger, a housing member surrounding said plunger having a dog receiving interruption therein, a dog on said plunger adapted to (be received in said housing interruption to permit said lplunger being depressed to actuate a switch, and a spring normally rotating said plunger so as to dis-align said dog with said housing interruption so that said plunger cannot be depressed to actuate a switch without rotating said plunger.

9. An electrical switch actuating safety button positioning said dog out of alignment with said a rotatable plunger disposed in said housingga I dog on said'plunger '50 disposed that when aligned withsaid housing interruption the button is operable and when dis-aligned with said housing interruption the button is inoperable, and a spring;

normally disalignin'g said dog with said housing" 15 12,434,012 interruption.

ELMO D. BLAKEMORE.

.aREFERENCES CITED The following "references are of record in the 'fileof this patent:

UNITED STATES PATENTS Number Name Date 1,161,477 Horton Nov. '23, 1915 v1,266,319 Riddell' May 14, 19 8 12,202,721 Andersen -May 28, 1940 2,241,122 Drotning May 6, 1941 2,377,691 Ja'ndus June-'5, 1945 2,420,768 Beveridge May 20, 1947 32,432,476 -Hesse Dec, 9,-1947 Ponti Jan: 6, 1948 

